protective tube

Abstract

To provide a protective tube that can be easily attached to a linear body such as a cable and has good workability.SOLUTION: A protective tube 1 is formed by arranging a pair of half-split tube bodies 2 so that their recessed surface sides are opposed to each other. The half-split tube body 2 includes a straight tube section 3 formed in a semi-cylindrical shape, a small-diameter connection section 4 at a rear end of the straight tube section 3, a large-diameter connection section 5 at a front end, and an engagement section 6 for engaging the pair of half-split tube bodies 2 with each other. The engagement section 6 has a projection section 7 provided at one edge section of the large-diameter connection section 5 and a holding section 8 for holding the projection section 7 provided at the other edge section of the large-diameter connection section 5. The holding section 8 has a hook-like section 80 for holding the projection section 7 of the opposed half-split tube body 2 so as to surround it, and opens front and rear surfaces of the projection section 7 without holding them.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a protective pipe for covering and protecting a linear body such as a cable.

Background Art

[0002] Conventionally, cables laid or buried under the sea have been used as transmission lines for communication or power from island to island. Such cables are generally covered and protected by a protective pipe in order to prevent damage caused by contact with rocky reefs or the like due to being washed by ocean currents and waves, or contact with the bottom of passing ships or anchors lowered from ships.

[0003] Such a protective pipe is formed, for example, in a cylindrical shape by arranging a pair of split pipe bodies facing each other. To attach the protective pipe to a cable, a pair of split pipe bodies are arranged so as to cover the side circumference of the cable from one side and the other side, and these split pipe bodies are fixed to each other with bolts (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, with the above-described protective pipe, the work of fixing a pair of split pipe bodies with bolts is very laborious, and the workability is not good. For example, in an environment with low seawater transparency such as the seabed with a lot of mud and sludge, underwater workers may sometimes be forced to work almost by groping, and it may be difficult to screw in the bolts.

[0006] The present invention solves the above problems, and an object thereof is to provide a protective pipe that can be easily attached to a linear body such as a cable and has good workability. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides a protective tube comprising a pair of split tubes arranged so that their concave sides face each other, wherein each split tube has a straight tube portion formed in a semi-cylindrical shape, a small-diameter connecting portion provided at the rear end of the straight tube portion and having a larger diameter than the straight tube portion, a large-diameter connecting portion provided at the front end of the straight tube portion and connecting to the small-diameter connecting portion of the other protective tube, and an engaging portion provided on the outer edge of the joint surface between the opposing large-diameter connecting portions to engage the pair of split tubes with each other, wherein the engaging portion has a protruding portion provided on one edge of the large-diameter connecting portion and the large-diameter connecting portion The other end of the pipe has a holding portion provided on the other end to hold the protruding portion of the opposing half-pipe body, the protruding portion having a first surface having a height difference in the positive direction with respect to the joint surface, a second surface parallel to the first surface, a third surface forming the front surface of the protruding portion, a fourth surface forming the rear surface of the protruding portion, and a fifth surface perpendicular to the first to fourth surfaces and forming the protruding end surface of the protruding portion, the holding portion has a hook-shaped portion that holds the first, second and fifth surfaces of the protruding portion of the opposing half-pipe body so as to surround it, and opens the third and fourth surfaces without holding them. Furthermore, the first and third surfaces are connected by a forward-curving surface, and the second and fourth surfaces are connected by a backward-curving surface. It is characterized by the following:

[0009] In the protective tube described above, it is preferable that the holding portion guides the protruding portions of the opposing half-tube bodies to the hook-shaped portion and has an inclined piece that slides against the rear curved surface of the opposing half-tube bodies.

[0010] In the protective tube described above, the split tube body has a plurality of locking protrusions provided on the outer edge of the joint surface with the opposing straight tube section, two of which are provided on one edge of the straight tube section along the longitudinal direction of the straight tube section, and one on the other edge of the straight tube section, and when the pair of split tube bodies are connected, it is preferable that the front and rear surfaces of the one locking protrusion provided on the other edge of the straight tube section are clamped by the two locking protrusions provided on one edge of the straight tube section.

[0011] In the protective tube described above, of the two locking protrusions provided on one edge of the straight pipe section, the locking protrusion provided at the front is preferably formed to be wider than the locking protrusion provided at the rear.

[0012] In the protective tube described above, it is preferable that the pair of split tube bodies have the same shape. [Effects of the Invention]

[0013] According to the protective tube of the present invention, the protruding portion of one half-tube is surrounded by the hook-shaped portion of the holding portion of the other half-tube, thereby restricting vertical displacement of the pair of half-tube bodies. Furthermore, since the first surface of the protruding portion is higher than the joint surface of the half-tube bodies, the wall formed by these steps comes into contact with the hook-shaped portion, thereby restricting horizontal displacement. Moreover, since the pair of half-tube bodies are not restricted in the front-to-back direction, the protruding portion and the holding portion can be engaged by sliding and rotating the upper half-tube body. Therefore, the protective tube can be easily attached to a linear body such as a cable by the simple operation of sliding and rotating the half-tube bodies without using bolts or nuts. [Brief explanation of the drawing]

[0014] [Figure 1] A partially exploded perspective view of a protective tube according to one embodiment of the present invention. [Figure 2] A perspective view of the pair of halved pipe bodies that make up the protective tube shown above. [Figure 3] Perspective view of the above-mentioned split pipe at a different angle than Figure 2. [Figure 4] (a) is a left side view of the split pipe shown above, (b) is a top view of the split pipe, (c) is a right side view, (d) is a cross-sectional view corresponding to (c), (e) is a bottom view, (f) is a front view, and (g) is a rear view. [Figure 5] A perspective view showing the procedure for connecting multiple protective tubes in a straight line. [Figure 6] (a), (b), and (c) are side views illustrating the procedure for connecting multiple protective tubes to each other. [Figure 7] (a), (b), and (c) are side views illustrating a different procedure than that shown in Figure 6. [Figure 8] (a) is a perspective view of the protective tube, (b) is a right side view, and (c) is a cross-sectional view. [Modes for carrying out the invention]

[0015] A protective tube according to one embodiment of the present invention will be described with reference to the drawings. As shown in Figure 1, the protective tube 1 is formed in a substantially cylindrical shape as a whole and is composed of a pair of halved tube bodies 2 that are cut in half by a plane including the cylindrical axis. The material of the protective tube 1 is not particularly limited as long as it has sufficient rigidity and durability to adequately protect the object to be protected over a predetermined period of time, for example, it may be made of resin or cast iron.

[0016] A pair of split pipes 2 have the same shape and are arranged so that their concave sides face each other, covering the side circumference of a linear body such as a cable C from two directions. When the pair of split pipes 2 are connected to each other, they come into contact at the joint surfaces 20 that form both ends of the concave surfaces of each. In the illustrated example, the linear body is a single cable C with a circular cross-section, but it may also be multiple cables, cables with an elliptical or flattened cross-section, or water pipes or gas pipes. In the following explanation, the split pipe 2 that is connected first will be referred to as "front," and the split pipe 2 that is connected next will be referred to as "rear." In the illustrated example, the left direction is referred to as "front," and the right direction as "rear."

[0017] The split pipe body 2 has a straight pipe section 3 formed in a semi-cylindrical shape, a small-diameter connecting section 4 provided at the rear end of the straight pipe section 3 in the cylindrical axis direction, and a large-diameter connecting section 5 provided at the front end of the straight pipe section 3 in the cylindrical axis direction. The small-diameter connecting section 4 has a structure with a larger diameter than the straight pipe section 3 and is formed by a flange in the illustrated example. The large-diameter connecting section 5 is formed in a bag-like shape with a larger diameter than the straight pipe section 3, for example, in a semi-cylindrical or hemispherical shape, and is connected to the small-diameter connecting section 4 of another protective pipe 1 as described later.

[0018] Further, the split pipe body 2 is provided at the outer edge of the joint surface 20 of the large-diameter connection part 5 and has an engaging part 6 for engaging the pair of split pipe bodies 2 with each other. The engaging part 6 has a protruding part 7 provided at one edge part of the large-diameter connection part 5 and a holding part 8 provided at the other edge part of the large-diameter connection part 5 for holding the protruding part 7.

[0019] As shown in FIGS. 2, 3, and 4(a) to (g), the protruding part 7 is a short columnar member that protrudes laterally parallel to the joint surface 20 from a position slightly forward of the front end part of the large-diameter connection part 5. The protruding part 7 has a first surface 71 having a positive height difference (step) with respect to the joint surface 20, a second surface 72 that is parallel to the first surface 71 and faces the first surface 71, a third surface 73 that forms the front surface of the protruding part 7, a fourth surface 74 that forms the rear surface of the protruding part 7, and a fifth surface 75 that is orthogonal to the first surface 71 to the fourth surface 74 and forms the protruding end surface of the protruding part 7. Here, the "positive direction" refers to the direction facing the opposing split pipe body.

[0020] The first surface 71 and the third surface 73 at its front end are connected by a gently rounded forward curved surface 76. The first surface 71 and the fourth surface 74 at its rear end are connected by a corner. Also, the second surface 72 and the fourth surface 74 at its rear end are connected by a rearward curved surface 77. The second surface 72 and the third surface 73 at its front end are connected by a corner. The corners of the first surface 71 to the fourth surface 74 and the fifth surface 75 are chamfered.

[0021] The holding portion 8 has a hook-shaped portion 80 that holds the first surface 71, second surface 72, and fifth surface 73 of the protruding portion 7 of the opposing half-cut pipe body 2, surrounding them. The hook-shaped portion 80 consists of a receiving piece 81 that bulges laterally with a negative height difference (step) relative to the joint surface 20, an upright piece 82 that is erected from the receiving piece 81 toward the opposing half-cut pipe body 2, and a stopper piece 83 that is bent inward toward the half-cut pipe body 2 from the upright end of the upright piece 82. In other words, the hook-shaped portion 80 is configured such that the receiving piece 81, the upright piece 82, and the stopper piece 83 are arranged in a U-shape. The step difference between the receiving piece 81 and the joint surface 20 corresponds to the step difference between the first surface 71 of the protruding portion 7 and the joint surface 20. When the opposing halved pipe bodies 2 are connected, the receiving piece 81 abuts against the first surface 71 of the opposing protruding portion 7, the upright piece 82 abuts against the fifth surface 75, and the stopping piece 83 abuts against the first surface 72. In other words, three surfaces of the protruding portion 7 are held by the hook-shaped portion 80, and the vertical and horizontal positional displacement shown in Figure 1 is restricted. On the other hand, the third surface 73 and the fourth surface 74 of the opposing protruding portion 7 are open and not held by the hook-shaped portion 80. In other words, they are not restricted in the front-to-back direction shown in Figure 1.

[0022] The receiving piece 81 of the holding part 8 is provided along the large-diameter connecting part 5. The holding part 8 also has an inclined piece 84 that guides the protruding parts 7 of the opposing half-pipe bodies 2 to the hook-shaped part 80 and slides against the rear curved surface 77 of the opposing half-pipe bodies 2. The corner of the stopper piece 83 opposite the inclined piece 84 is a curved surface 85 (see Figure 2, and also Figures 6(a) and 6(b) described later). Furthermore, a wall portion 78 is formed by the step difference between the joining surface 20 and the first surface 71, and a wall portion 86 is formed by the step difference between the joining surface 20 and the receiving piece 81 (see Figure 3 in particular). The wall portion 78 faces inward, and the wall portion 86 faces outward, and when the opposing half-pipe bodies 2 are connected, these wall portions 78 and 86 come into contact (see also Figure 8(c) described later). This restricts the lateral displacement that was not restricted by the three surfaces of the protruding part 7. Furthermore, since the receiving piece 81 is recessed relative to the joining surface 20, a wall portion 87 is formed behind the inclined piece 84. This wall portion 87 abuts against the wall portion 79 that forms the opposite side of the wall portion 78, thereby more reliably restricting misalignment in the left-right direction.

[0023] Furthermore, each half-pipe body 2 has a plurality of locking protrusions 9 provided on the outer edge of the joint surface 20 with the straight pipe section 3 of the opposing half-pipe body 2. These locking protrusions 9 consist of two locking protrusions 9a and 9b provided along the longitudinal direction of the straight pipe section 3 on one edge of the straight pipe section 3, and one locking protrusion 9c provided on the other edge of the straight pipe section 3. When a pair of half-pipe bodies 2 are connected, the front and rear surfaces of the one locking protrusion 9c provided on the other edge of the straight pipe section 3 are clamped by the two locking protrusions 9a and 9b provided on one edge of the straight pipe section 3 (see Figure 1). In addition, of the two locking protrusions 9a and 9b, the locking protrusion 9a provided at the front is formed to be wider than the locking protrusion 9b provided at the rear.

[0024] Next, the procedure for connecting a pair of split pipes 2 in the protective pipe 1 configured as described above will be explained. Here, as shown in Figure 5, the rear-next-door lower split pipe 2A is positioned below the small-diameter connection portion 4 of the front-next-door protective pipe 1, covering the lower half surface of the cable C, and the explanation will be based on the example in which the rear-next-door upper split pipe 2B is connected to this rear-next-door lower split pipe 2A. In the protective pipe 1 of this embodiment, the split pipes 2A and 2B can be connected by two patterns: a front sliding pattern (solid arrow) in which the rear-next-door upper split pipe 2B is slid from front to rear to connect to the rear-next-door lower split pipe 2A, and a rear sliding pattern (dotted arrow) in which the rear-next-door upper split pipe 2B is inserted from rear to front to connect to the rear-next-door lower split pipe 2A.

[0025] Figures 6(a) to 6(c) show the procedure for connecting the split pipe bodies 2A and 2B using a forward sliding pattern. Here, the configuration of the protruding part 7 and the holding part 8 is partially visualized from a viewpoint on the right side of the protective pipe 1. As shown in Figure 6(a), the large-diameter connecting part 5 of the rear-adjacent upper split pipe body 2B is placed on top of the straight pipe part 3 of the front-adjacent protective pipe 1, and with the small-diameter connecting part 4 side lifted, the rear-adjacent upper split pipe body 2B is slid backward. The upper split pipe body 2B is positioned at an angle of, for example, 20 to 40° with respect to the lower split pipe body 2A.

[0026] The right side view shown in Figure 6(a) shows an example configuration in which the protruding part 7 (hatched) of the lower half-tube body 2A is aligned with the holding part 8 of the upper half-tube body 2B. However, on the left side view, which is not shown, the protruding part 7 of the upper half-tube body 2B is aligned with the holding part 8 of the lower half-tube body 2A.

[0027] As the upper half-tube 2B is slid backward, as shown in Figure 6(b), the retaining piece 83 of the holding part 8 of the upper half-tube 2B passes under the protruding part 7 of the lower half-tube 2A. At this time, since the rear corner of the retaining piece 83 is a curved surface 85, the retaining piece 83 can smoothly pass under the protruding part 7 while sliding in contact with the lower surface of the protruding part 7.

[0028] Next, the upper half-pipe 2B is rotated so that the small-diameter connection part 4 is tilted, thereby reducing its inclination and connecting the upper half-pipe 2B to the lower half-pipe 2A. Here, the protruding part 7 of the lower half-pipe 2A is provided with a rearward curved surface 77, and the stopper piece 83 of the upper half-pipe 2B is provided with a curved surface 85, so that the upper half-pipe 2B can be rotated smoothly.

[0029] When the upper half-pipe 2B is placed facing the lower half-pipe 2A, the second surface 72 of the protruding portion 7 of one half-pipe 2 comes into contact with the stopper piece 83 of the other half-pipe 2, thereby restricting the vertical movement of the ends (front ends) of the half-pipe 2A and 2B on the large-diameter connecting portion 5 side. At this time, the small-diameter connecting portion 4 of the adjacent protective pipe 1 is covered by the large-diameter connecting portion 5 of the adjacent protective pipe 1, so the ends (rear ends) of the small-diameter connecting portion 4 of the adjacent protective pipe 1 are also restricted from moving vertically and horizontally, completing the fixing of the adjacent protective pipe 1. In addition, the wall portion 78 and the wall portion 86 come into contact, and the wall portion 79 and the wall portion 87 come into contact. This also restricts the horizontal displacement of the front end of the half-pipe 2 (see Figures 8(a) and 8(c) described later).

[0030] Furthermore, the locking projection 9c of the upper half-pipe 2 fits between the locking projections 9a and 9b of the lower half-pipe 2. This restricts the front-to-back displacement of the half-pipe 2A and 2B. Also, since the locking projections 9a, 9b, and 9c all protrude vertically beyond the joint surface 20 of the straight pipe section 3, the left-to-right displacement of the half-pipe 2A and 2B is also restricted. In this state, the vertical displacement of the small-diameter connection section 4 side end (rear end) of the half-pipe 2A and 2B is not restricted, but by placing the large-diameter connection section 5 of the adjacent protective pipe 1 over it, the vertical displacement of this rear end can also be restricted.

[0031] Next, Figures 7(a) to 7(c) show the procedure for connecting the split pipes 2A and 2B using a rearward sliding pattern. In the rearward sliding pattern, as shown in Figure 7(a), the upper split pipe 2B is tilted slightly behind the lower split pipe 2A, and its front end is brought into contact with the straight pipe section 3 of the protective pipe 1 adjacent to the front. Then, the upper split pipe 2B is slid in from rear to front so that its stopper piece 83 fits under the protruding portion 7 of the lower split pipe 2A.

[0032] In the right side shown in Figures 7(a) to (c), the stopper piece 83 of the upper half-tube body 2B is inserted under the protruding portion 7 of the lower half-tube body 2A. However, on the left side, the protruding portion 7 of the upper half-tube body 2B is inserted under the stopper piece 83 of the lower half-tube body 2A (see Figure 2). At this time, the holding portion 8 is provided with an inclined piece 84, which allows the protruding portion 7 to be smoothly guided to the hook-shaped portion 80.

[0033] Next, as shown in Figure 7(b), the upper half-tube body 2 is slid to a position where the upper stopper piece 83 contacts the lower projection 7, and then rotated. Then, as shown in Figure 7(c), the upper half-tube body 2B is brought facing the lower half-tube body 2A. This allows the half-tube bodies 2A and 2B to be connected in the same way as the forward sliding pattern.

[0034] Figures 8(a) to 8(c) show the protective tube 1 in which a pair of split pipe bodies 2 are connected. In this way, in the protective tube 1 of this embodiment, the protruding portion 7 is surrounded by the hook-shaped portion 80 of the holding portion 8, so that the vertical displacement of the pair of split pipe bodies 2 can be restricted. Also, since the first surface 71 of the protruding portion 7 is higher than the joint surface 20 of the split pipe bodies 2, the wall portion 78 formed by these steps comes into contact with the wall portion 86, and the wall portion 79 and the wall portion 87 come into contact, so that the horizontal displacement can be restricted. In addition, the locking projections 9a, 9b, and 9c can restrict the front-to-back and left-to-right displacement of the pair of split pipe bodies 2. Furthermore, when the locking projections 9a, 9b, and 9c are not engaged, the pair of split pipe bodies 2 are not restricted in the front-to-back direction, so the upper split pipe body 2 can be slid as shown in Figures 6 and 7. Then, by bringing the protruding part 7 and the holding part 8 close together and rotating the upper half-pipe body 2, the protruding part 7 and the holding part 8 can be engaged. In this way, with the protective pipe 1 of this embodiment, the protective pipe 1 can be easily attached to a linear body such as a cable by a simple operation of sliding and rotating the half-pipe body 2 without using bolts or nuts. Such an operation can be done almost by feel, and the worker can easily install the protective pipe 1 even in environments with low transparency of seawater, such as swamps or the seabed with a lot of sludge. Furthermore, as described above, since a forward sliding pattern or a backward sliding pattern can be used, the procedure for connecting the half-pipe body 2 can be switched, for example, depending on the terrain of the installation site.

[0035] Furthermore, the pair of halved tube bodies 2 that make up the protective tube 1 are identical in shape. Therefore, workers working underwater do not need to distinguish whether a halved tube body 2 is for the upper or lower section, and workers on board the ship can continuously supply halved tube bodies 2 to workers underwater, improving work efficiency. In addition, there is no need to prepare multiple molds for forming the halved tube bodies 2, thus improving the manufacturing efficiency of the halved tube bodies 2.

[0036] It should be noted that the protective tube according to the present invention is not limited to the above embodiment and can be modified in various ways. The protective tube 1 of this embodiment is characterized by the fact that the split pipe bodies 2 can be connected without using bolts or nuts, but bolt holes (not shown) can be provided as appropriate so that bolts and nuts can be used. In particular, the end (rear end) of the last split pipe body 2 on the small diameter connection part 4 side is not fixed as is because there is no adjacent part after it. The unfixed end can be fixed with cable ties or the like, but a modified example in which a bolt hole is provided at the end on the small diameter connection part 4 side may be adopted. [Explanation of Symbols]

[0037] 1 Protection tube 2, 2A, 2B Half tube body 20 Joint surface 3 Straight pipe section 4. Small diameter connection section 5. Large diameter connection section 6 Engaging part 7 Protrusion 71 Page 1 72 2nd page 73 Page 3 74 Page 4 75 Page 5 76 Forward curved surface 77 Back curved surface 8 Holding part 80 Unicum 84 Inclined piece 9Aa, 9b, 9c Locking protrusion

Claims

1. A protective tube formed by arranging a pair of halved pipe bodies so that their concave sides face each other, The aforementioned split pipe body has a straight pipe section formed in a semi-cylindrical shape, a small-diameter connecting section provided at the rear end of the straight pipe section and having a larger diameter than the straight pipe section, a large-diameter connecting section provided at the front end of the straight pipe section and connecting to the small-diameter connecting section of the other protective pipe, and an engaging section provided on the outer edge of the joint surface between the opposing large-diameter connecting sections to engage the pair of split pipe bodies with each other. The engaging portion has a projection provided on one edge of the large-diameter connecting portion and a holding portion provided on the other edge of the large-diameter connecting portion for holding the projection of the opposing half-pipe body. The projection has a first surface having a height difference in the positive direction with respect to the joint surface, a second surface parallel to the first surface, a third surface forming the front surface of the projection, a fourth surface forming the rear surface of the projection, and a fifth surface perpendicular to the first to fourth surfaces and forming the projection end surface of the projection. The holding portion has hook-shaped parts that hold the first, second, and fifth surfaces of the protruding parts of the opposing split pipe bodies, while leaving the third and fourth surfaces open without holding them. The first and third surfaces are connected by a forward-curving surface. A protective tube characterized in that the second and fourth surfaces are connected by a rearward curved surface.

2. The protective tube according to Claim 1, characterized in that the holding portion has an inclined piece that guides the protruding portion of the opposing half-tube body to the hook-shaped portion and slides against the rear curved surface of the opposing half-tube body.

3. The split pipe body has a plurality of locking protrusions provided on the outer edge of the joint surface with the opposing straight pipe portion, The aforementioned locking projections are provided as follows: two along the longitudinal direction of the straight pipe section on one edge of the straight pipe section, and one on the other edge of the straight pipe section. The protective tube according to claim 1, characterized in that when the pair of halved tubes are connected, the front and rear surfaces of the one locking projection provided on the other edge of the straight tube are clamped by the two locking projections provided on one edge of the straight tube.

4. The protective tube according to claim 3, characterized in that of the two locking protrusions provided on one edge of the straight tube portion, the locking protrusion provided at the front is formed to be wider than the locking protrusion provided at the rear.

5. The protective tube according to any one of claims 1 to 4, characterized in that the pair of halved tube bodies are the same shape as each other.

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